It's better and more sustainable to shoot for a -500kcal/day deficit AFTER your basal calories + activity calories are added back.
One easy way to roughly approximate this is to use
11 kcal x (body weight in lbs) as a BASE (you need to add exercise cals on top of this)
So, a 150lbs guy would shoot for a non-exercise caloric intake base of 1600 kcal.
You then have to add your exercise calories ON TOP of this 1600.
So if you burn 800 cals exercising, your total daily calorie intake will be 1600+800 = 2400 total. You should be close enough to -500kcal/day at this range, and it's very sustainable. I do it with no loss of performance or fatigue during training.
I'd avoid any big-calorie drop diets unless you're really overweight - they are simply unsustainable for the 3-6 month period you really need to be shooting for to get meaningful weight losses.
If you do a fixed '2000kcal/day', you'll have big mismatches with intake and calorie burning when on off/light days vs big-load days (like a 3hr bike) where you might burn 2000 kcal alone exercising.